Clarke CL500M longitudinal feed screw

Hi,

Does anyone know if the nut on the longitudinal feed screw is adjustable and if so is it supposed to look like this? I'm wondering if there is supposed to be a bolt and it has sheared off. I tried a few different allen keys in the hole to see if there is an allen screw in there but doesn't seem to be?

Thanks Stuart

Yes that type of nut with the slot is to take out thread play. lash. By nipping the bolt it squeezes the leadscrew & removes the play. Unless i am wrong.!!!

Steve.

Edited By Steviegtr on 03/01/2021 14:16:15

Thats what I figured Steve, but I can't see how I can squeeze the two halves together without a nut head or alllen screw head?

I have only seen them & not adjusted one. So do you have a grub screw that pushes the gap apart or a bolt that pulls them together. Sure some one will be along shortly that has done this.

Steve.

Have you had a look at these drawings.

Clarke lathe PDF

Steve.

Thanks, yes I have, but there is no mention of an adjusting screw, just part no 54 which is the complete feed nut 🤔

So assuming you've found an allen key goes right through, what stops you buying a screw pack from B&Q and fitting it?

Whatever size fits. just be gentle with it, you need some lash or the thread locks.

There should be a screw to open out the slot and take up most of the backlash. It's in the other end of the photo - unless it's missing

Thanks Dave, thanks John.

I have just been digging around and found a load of crud covering an allen bolt head the other side of the nut. It was solid crud, almost like body filler and flush with the surface of the nut, so it completely camouflaged the bolt head. Anyway I have dug it all out and managed to tighten the bolt and take out quite a bit of back lash.

I don't think it has ever been adjusted. I didn't over tighten the bolt and made sure the threads still run freely.

Problem sorted!

Thanks Stuart

I have absolutely no experience of these machines but understand the principle of the backlash adjustment. I would have thought any adjustment screw would be fitted from the exposed end shown in the image as the extra thickness provides more support to the adjusting screw. The narrower (thinner section) is also more likely to be deflected to achieve the adjustment required. Is the screw missing, or if of allen screw configuration is it just that the hex is smaller/larger than anticipated - or even a slot head screw?

Robert Butler

Edited By Robert Butler on 03/01/2021 17:32:56

Thanks Robert. See above

Stuart, these lathes were typically bought by the unknowing - never adjusted before purchase, and never set up after purchase, so they have a reputation of being sloppy and poorly made. You will find however that with proper adjustment, and there are many adjustment features, your lathe will likely work well and accurately.

Our forebears produced splendid work on machines lacking even the features of the CL500M.

A skilled man can produce good work on a poor machine. An unskilled one can produce poor work on a good machine. I bear witness to that!

Many a good tune and all that.

Once it is sorted and you are familiar with the machine you will be surprised what you can do with it.. You just have to recognise the limitations and work within them. Add few "bespoke" accessories and even more will be possible.

Saddle Stop and Centre Height Gauge spring to mind as being useful in the very near future.. Then Tailstock Die, and Tailstock Tap holders, even Floating Reamer Holders, and a Tailstock Drilling pad could be added to the list..

The Milling facility would allow you to make your own Tangential Turning Tool holders.

The world is about to become your oyster!

Howard

They appear to have a substantial compound slide, which is one area that seems to be lacking in many smaller far eastern machines.

Stuart,

The cross slide uses the same adjustment, I regularly squirt oil along the leadscrew, do you have two metal gaurds fitted to the traverse casting covering the leadscrew these keep most of the muck off the thread.

I've just noticed you asked for the name of my VFD, I will pm the details.

Martin P

Oops

Edited By martin perman on 04/01/2021 18:03:41

Thanks for the encouragement Howard

Do you mean the telescopic looking metal guards Martin? I don't have any covering on the lead screw at the moment but have considered adding something

Stuart,

The ones fitted to my lathe are mounted above the lead screw and are attached to the traverse casting either side and are held in place by one screw each, they are a length of metal sheet about 5" long covering the leadscrew, they are not shown on the drawings, something else for me to remember I will photograph them on Thursday and PM you them, part time job and other duties dont allow sooner

Martin P

Thanks Martin, much appreciated